Ink-distributing device for printing-presses.



No..7o0,'2eo. v Patented May 29;;1902

I J. THOMSON. i 1 INK DISTRIBUTING DEVICE FOR PRINTING PBESSES.

(Application filed July 1, 1901.)

(No Model.)

FEE v k fllnlpl llm mllllllllllllllhw UNiTED STATES PATE T OFFICE.

JOHN THOMSON, on NEW YORK, N. Y., ASSIGNOR-TO JOHN THOMSON PRESS COMPANY, OF NEW YORK,

N. Y. A CORPORATION OF NEW JERSEY.

INK-DISTRIBUTING DEVICE FOR PRINTING-PRES'SE S.

SPECIFICATION forming part of Letters Patent N 0. 700,260, dated May 20, 1902.

Application filed July 1, 1901. Serial No. 66,715. on; man.) i

T0 at whom, it may concern.-

Be it known that I, JOHN THOMSON, a citizen of the United States, residing at New York, in the county and-State of New York, have invented certain new and useful Improvements in Ink-Distributing Devices for Printing-Presses, of which the following is a specification.

My invention relates to ink-distributing devices for printing-presses, and more particularly to the self-contained type of distributing-roller known as the duplex screw distributeror changer; and it has for its object to provide an improved construction which shall involve theleast amount of friction and provide the greatest extent of bearing-surface, hence increasing the durability,

and which, moreover, shall be inexpensive to construct. V

To these ends my invention consists in a changer distributing-roller embodying the features of construction substantially as hereinafter more particularly set forth.

Referring to the accompanying drawings,

Figure 1 is a plan view of the changer-sleeve. Fig. 2 is an end view thereof. Fig. 3 is aside and end view of the changer hollow screw.

Fig. 4 is a side and end view of the changer crescent as previously constructed. Fig. 5-

is a plan and end view of the changer screwshaft, and Fig. 6 is a side and end view of the changer-crescentof improved construction.

It is well known by those skilled in the art that in the prior construction of the duplex or cross-screw changer there is excessive wear of the parts, producing loose joints and broken parts, which result in loss of efiectiveness and increased cost ofmaintenance. It is the object of my present invention to provide means which shall efiectually overcome these objections, and this I have accomplished by a construction substantially such as herein described.

Referring'to the. accompanying A represents the changersleeve.

drawings, The

changer-shaft, as B, is provided at each end with a duplex or cross screw, right and left pitch, as O D. The hollow screws E, mounted transversely in the ends of the sleeve, pro- It will be seen that I use two crescents, one

at each end of the changer-sleeve, each 00- operating with itsindependent duplex thread on the changer-shaft, and it is manifest that in order to produce satisfactory results these, crescents must 'coact harmoniously. Thus in making the compound threaded shaft it is necessary that the pitch of both the duplex threads shall be exactly alike and that the starting and ending of both threads of each of the duplex sections shall be on the same horizontal line. The result of this is to donble the area of the bearing-surface, both in the crescents and in the sides of the threads, without materially increasing the work or resistance to be overcome. Consequently the advantage derived is increased durability and lessened cost of maintenance. that a still further increase in the endurance and efllciency of the apparatus may be accomplished by increasing the time of reversal-that is, when the crescent: is swung on its spindle F and the changer-sleeve is started back-and by changing the form of the crescent. Heretofore that portion of the thread Where the crescent swings on its spindle has been a channel of the same width as the rest of the thread, as at J, which has necessitated that the crescent shall be of wedgeshaped section, as at K, Fig. 4, to permit it to pass this portion of the thread; but by cutting away the inside wall, as at P, widening the slot where the reversal takes place, it be comes'feasible to use a crescent with parallel sides, as B, Fig. 6, thus increasing the time of the reversal, decreasing the shock, and in- I have found creasing the area of bearing-surface, increas- 5 of embodying the same, what I claim is- In a printing-press, the combination with I name to this specification in the presence of the changer-sleeve, hollow screw and crestwo subscribing Witnesses. cent, of the changer screw-shaft, the duplex thread, or threads, of which are cut away, as

5 at P, to effect a relatively slow reversal of the changer-sleeve, substantially as described.

In testimony whereof I have signed my JOHN THOMSON.

\Vitn esses:

HELEN M. BLANCHFIELD, SAML. II. WEBB. 

